1. Field of the Invention
The present invention relates to a lithium-ion secondary battery.
2. Related Background Art
Known as a lithium-ion secondary battery is one using a negative electrode active material containing elemental silicon or a silicon-containing alloy or a silicon-containing oxide, which has been supposed to yield a theoretical capacity higher than that of a graphite negative electrode (see, for example, Japanese Patent Application Laid-Open Nos. 2009-110798, 2005-63772, 2006-294519, 11-307120, and 2008-10414).